AmigaOS 4.0 MUST have icons with two states (not just glow or whatever). That's one of the things that caracterize Amiga.
When I click a drawer I want to see it open not just ghosted like in other OSes. I like glowicons but only when they have a second state i.e. the ram disk icon.
So if they make PNG icons for the Amiga they better have a second Amiga-like state when they are clicked.